MR expression in human platelets. (A) Protein extracts from washed platelets or HEK cells were prepared as detailed in “Materials and methods” and analyzed by WB for MR expression; a band corresponding to the expected MW was observed. Blot is with samples from 3 distinct cell preparations, and it is representative of 3 separate experiments. (B) Washed platelets were permeabilized with saponin (“Materials and methods”) and stained with FITC-conjugated antibody to MR or Cy5-conjugated anti-GR antibody. (Bi) Negative primary antibody control; (Bii) positive staining for MR; (Biii) positive staining for GR; and (Biv) 2-color staining demonstrating platelet dual positivity for MR and GR (representative of data from 3 donors).